A liquid ejection device (liquid ejection head) is configured to change pressure in a region filled with liquid (pressure chamber) to eject a liquid droplet from a nozzle. A drop-on-demand liquid ejection head is most popular and is used in an inkjet printer for printing a document or an image or the like.
Liquid ejection systems are broadly divided into two systems. One of the systems is a system in which a capacity of the pressure chamber is changed by applying a voltage to an electromechanical coupling element represented by a piezoelectric element, to thereby eject liquid. The other of the systems is a system in which a resistor produces heat by a voltage applied thereto to generate an air bubble in the pressure chamber, to thereby eject liquid.
In recent years, a liquid ejection device for an industrial use is required to eject liquid with an extremely high degree of precision. For example, liquid ejection on the order of picoliters is required. Further, liquid ejection even on the order of subpicoliters or smaller is required.
A technology involving changing a capacity of a pressure chamber (ink channel) by displacing a partition formed of a piezoelectric material in a shear mode, to thereby eject liquid, can precisely control the capacity change of the pressure chamber, and thus has attracted great attention.